Sulindac, chemically cis-5-fluoro-2-methyl-1-[(p-methylsulfenyl)benzylidene [indene-3-acetic acid, is a non-steroidal anti-inflammatory agent which is marketed only in 150 gm. and 200 mg. tablets for oral administration 1-3 times daily (Physician's Desk Reference 1987, p.1251). The parent acid is very insoluble in water and especially in methyl or ethyl alcohol (Merck Index 10th Edition, 1983, p.1290). The compound is erratically absorbed from the gastrointestinal tract. Oral liquids of sulindac have not been easily available to the medical art because of the bitter taste of the drug. U.S. Patent Number 3,654,349 discloses a number of pharmaceutical forms of sulindac, column 4, lines 3-25. The sodium and calcium salts are described in Examples 16 and 17 of the patent as being prepared by the reaction of the parent acid with the respective alkali metal methoxide in methanol.
There is a need in the pharmaceutical art for an elegant, oral liquid composition of sulindac for treating patients who have difficulty ingesting solid compositions such as tablets or capsules.